It said: “It has become part of the culture in public life that individuals are entitled to capitalise on their public sector experience when they move into the private sector — the “new normal” — but there is a lack of clear boundaries defining what behaviour is or is not acceptable.”

The report called for a review of whether the rules set by Acoba could be written into law, which would make it illegal for ministers and civil servants to disregard rulings made by Acoba, which is currently only an advisory body.

It said that 600 former ministers and top-level civil servants had been appointed to 1,000 private sector roles between 2000 and 2014.

It also singled out former chancellor George Osborne for particular criticism, and said that his decision not to seek approval from Acoba before he was appointed as the editor of the Evening Standard in March had set an “unhelpful example.”

It said: “We disapprove of the announcement of Mr Osborne’s appointment as editor of the Evening Standard without waiting for Acoba’s advice.”

“This demonstrates disrespect for Acoba and for the business appointment rules and sets an unhelpful example to others in public life who may be tempted to do the same.”

It also called out his £650,000-a-year advisory post at investment BlackRock, which it said had “increased concern” about about the trend of ministers accepting employment in sectors where they were previously responsible for policy, although it said that the committee had not taken particular evidence in the case.